Coulrophobia is a fear (phobia) of clowns. Children and adults who fear clowns may experience extreme, irrational reactions when they see clowns in person or view clowns' pictures or videos. Someone with a fear of clowns is coulrophobic. They may go out of their way to avoid any exposure to clowns. Awareness of coulrophobia is relatively new. The term coulrophobia first appeared in the late 1990s. "Coulro" is the Greek word for stilt walkers. Recent movies featuring creepy-looking clowns, like "It" and "Joker," made people more aware of this phobia.

Source: Cleveland Clinic